Orthodontic appliance and orthodontic system

An orthodontic appliance, comprising a main body portion and a traction component, a transmission component, and a position occupying component disposed independently of each other, wherein the main body portion is disposed with a trench and a containing cavity openly formed and connected to the trench, the traction component is detachably connected to the containing cavity and/or the transmission component;

• the containing cavity accommodates the transmission component, the position occupying component is disposed in the trench or disposed in the containing cavity and the trench, and the transmission component is linkagedly connected to the position occupying component;
• the transmission component is provided with a transmission fitting member, the transmission fitting member is configured to linkagely connect a screwing tool, and the transmission component drives the position occupying component to at least partially enter or exit the trench or move in the trench along a trench width direction to change an effective space of the trench.